In situ observations of fretting wear behavior in PMMA/steel model

Detailed fretting wear phenomena are usually hidden between the two contacted surfaces. Direct or in situ observation of fretting wear process is supposed to obtain some time-dependent changes and shed more light on the fretting wear mechanisms. In this paper, the fretting wear behaviour of a polymethyl methacrylate (PMMA) flat specimen in contact with a steel sphere has been investigated by in situ observation and numerical analyzed. Many tests were carried out using a specially designed piezoelectric fretting wear testing apparatus. The fretting wear crack initiation and propagation in PMMA flat specimen were monitored in real time using a laser profile-measuring microscope. It is found to be different with metal/metal contact model, the frequency of tangential loading has a big influence in the fretting wear damage processes of PMMA flat/steel sphere model.